1. Field of the Invention
The present invention relates generally to an optical device, and more particular to an optical coupling device.
2. Description of the Related Art
As the improvement of technology, more and more devices are designed for transmitting data through optical signals. Optical coupling device is one of the popular devices used in many fields.
U.S. Pat. No. 7,369,328 taught a conventional optical coupling device, in which an optical coupling member is provided between two optical connectors. The optical coupling member is respectively provided with a lens on opposite sides. A distance between the lens and a reflective surface is the same as the distance between the other lens and the reflective surface so that the optical coupling device may have a low signal loss and a high coupling efficiency in the optical coupling transmission when optical signals emit through the optical member and the lenses change the characters of the optical signals.
However, as the improvement of technology, the optical signals are designed to have various numerical apertures according to different requirements. When the optical signals with great numerical apertures emits through the conventional optical coupling device, the optical signals will be diffused to a margin of the lens that may increase the loss and distortion.
Therefore, the conventional optical coupling devices are designed for the optical signals with numerical apertures in a narrow range only. It will take a long time for alignment of the optical signals, and affect the locating accuracy of the optical coupling member. In conclusion, the conventional optical coupling device still needs to be improved.